Improvement in locomotive-boilers



UNITED STATES PATENT OEETCE.

BENJAMIN CRAWFORD, OF PITTSBUBQ-PENNSYLVANIA.

IMPROVEMENT IN LCOlS/lOTlVlE'.-BOlLEPtS.Y

Specification forming partrof Letters Patent No. l39,123, dated July 7, 1863.

To all whomz' may concern.'

Be it known th at I, BENJAMIN CRAWFORD, of Pittsburg, in the county of Allegheny and State ot' Pennsylvania, have invented a new and useful Improvement in Tubular Boilers for Locomotives, 85e.; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making a part of this specification, in which- Figure lis a longitudinal vertical section through a locomotive-en gine boiler having my improvement applied to it. Fig. 2 is a vertical diametrical section through Fig. l, taken at the point indicated by red line :v ao thereon. Fig. 3 is a side elevation of the forward end of the boiler and the superheating apparatus. (Seen by removing a portion of the shell of the boiler.)

Similar letters of reference indicate correponding parts in the three gures.

The nature of my invention consists in an arrangement of a superheater within the shell of a tubular or flue boiler in such a manner that the heated products of combustion escaping from the iiues oi' the boiler will immediately pass through the short tubes or lues, and thus cause these tlues to act as a superheater, and while this is the case the superheated steam is compelled to rise from the bottom of the superheatingchamber and escapefrom the chamber atapoint some considerable distance above the bottom, or near the top, of the superheating-chamber.

To enable others skilled in the art -to make and use my invention, I will proceed to describe its construction and operation.

The drawings illustrate the application of my invention to the boiler of alocomotive, in which A represents the nre-box; B, vthe cylindrical shell of the boiler; C,the steam-dome; D, the mainsteam-pipe; E,the smoke-box,and F the smoke-stack, all ot' which maybe constructed and arranged in the usual or most improved manner. Theiiues a a a open into the tire-box A, and conduct the highly-heated products of combustion in the direction indicated by the dark arrows in Fig. 1. These boiler-ilues terminate at the booilerhead b', between which and the smoke-box E is letta space for the introduction of a short section of boiler-lines, c c c, which are confined at their terminal ends t0 the circular heads d d', as shown in Figs. l

and 3, which are equal in diameter to and are conned in a suitable manner within the aforesaid space. Ihe iiues or tubes c are arranged between the heads d d in such a manner and in such relation to the boiler-dues t a aI that when the whole are placed within the shell B and properly adjusted these iiues o c c will all coincide with the flue-tubes a a a of the boiler, as represented in Figs. l and 3. In this way I secure a direct draft through all the lues a c, from the fire-box Al to the smoke-box E, and thence through the chimney F. Between the head d of the short section of lues c and the head b of the boiler is left a small space, e, for the purpose of allowing the heated gases escaping from the iiues a to ll this space and impinge upon the upper portion of the head d, and more thoroughly heat the chamber j' above the lues c, thus utilizing as far as possible the heat of the gases for superheating purposes. The forward end ofthe main steampipe D, which conducts away the steam from the boiler, terminates in the open space j above the lues c, and thus conducts the steam, which is highly impregnated with water, directly into this superheating-chamber, where the steam is deprived of its moisture by being subjected to the dry-heating intluence of the tubes c c and,thus reheated, the steam escapes through the branch pipe Gr, and is conducted by means of pipes leading from this branch pipe directly to the steam-chests ot' the engines in any convenient manner. The partition or diaphragm g separates the upper part of the superheater in two compartments, ff', the communication between which is under this diaphragm. The steam entering this superheater from the steam-pipe D will thus be compelled to descend and circulate through the spaces between the iiues c c, thence up and out through the exit-pipe G, as indicated by the course of the red arrows in Fig. l. It will be seen that, were this diaphragm removed, the steam would to a great extent es cape through the superheater without its producing the desired effect, as the heating-hues c c do not extend higher than those ot' the boiler. Steam taken from the boilers in the usual manner is always more or less saturated with water unevaporized. This water is not only unproductive of power in itself, but it actually lessens the @is @toa of the steam, as it produces more or less condensation ot' the steam, which goes on constantantly from the time it rises from the water in the boiler, and continues still more rapidly as it-passes through the cylinders. The object of the superheater is to more thoroughly vaporize the water contained in the steam, and to add sufficient heat to the steam to prevent anycondensation from taking place until after the steam passes through the cylinders. By this arrangement a vvery large amount of fuel will be saved, and a much less amount ot boiler-space will be required to produce a given amount of power, which, in the case of a locomotive-boiler, will enable them to be built much lighter, and consequcntly they will be much less destructive to the roads.

The arrangement, which l have shown and described, of a superheating apparatus within the common boiler-shell oi' a locomotive, so that the flues c c of this appparatus will form, with the boiler-iiues t ft a, direct passages from the iire box A to the smoke-box E, which arrangement constitutes the novelty of my invention. It will be seen by this arrangement that I am enabled to reduce the capacity of the boiler and make a very compact and light locomotive, all the ues of which may be readily got at from the forward end of the locomotive for cleaning out, repairing, &c.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is- Y l. The arrangement of the superheatingtubes c 0 in line with the tlues a a, when the chamber which contains the tubes c c is constructed with a vertical diaphragm, g, and the whole inclosed by the case B of the boiler, substantially as and fer the purpose set forth.

2. The combination of heads cl d', tlues c c, steam-pipes D Gr, and diaphragm j), arranged and operating substantially as herein described, and for the purpose set forth.

BENJ. CRAWFORD. Witnesses z M. M. BRIDE, J As. L. SUTHERLAND. 

